The rise of rapper Angel Haze was starting to look shaky as the 21-year-old tested fans' patience by postponing her UK tour twice — this media-friendly London date went ahead — to focus on her debut album.

In fairness, the Brooklyn rapper hasn’t been idle. She’s given away dozens of tracks online and this fearless performance felt potentially transformational for hip-hop.

From the opening Werkin’ Girls her rhyming was relentless and, like a prize fighter, she stripped down to a bra top for the breathless 50 minutes ahead of her.

Joined by a band and backing singers, Haze was more like a rock star than a surly rapper as she strode into the crowd for the suave Hell Could Freeze, recorded with Hackney chart-toppers Rudimental.

Only Haze could have got away with reinterpreting Jay Z and Kanye West’s No Church in the Wild as a strident, folkish duet with a violinist.

The most remarkable moment, though, was her reworking of Eminem’s Cleanin’ Out My Closet, performed for the first time because “London was the first place to show me love”.

Hunched in the shadows, Haze’s rap nightmare chronicled her own childhood sexual abuse in harrowing detail, building to a fierce, cathartic conclusion that had the audience cheering its support.

Haze was imperious on the encore of New York, featuring handclapping beats and her eccentrically autocratic claim to run the city where rap was born.

A riotous guest appearance by rapper Iggy Azalea ended with the pair leaping into the crowd and posing for photos. “She’s the future,” said Azalea of Haze. You couldn’t possibly doubt her.